Category Archive for: FIELD-EFFECT TRANSISTORS

General Algebraic Solution We can obtain general algebraic expressions for the bias points in POMS and NMOS circuits hy solving equation 7-llJ simultaneously with quondam 7-21 or 7-22 for If). ! results are The transfer characteristic of the FET in Figure 7-42 is given in Figure· 7-43 (fj = ll.5 X 10 -J ). Determine values…

Figure 7-36 shows a set of drain characteristics resulting from repetitions of the process we have described. with set 10 different values of positive voltage. When ViiS is reduced 10 the threshold voltage Vr = 2 V, notice that If) is reduced to 0 for al\ values of Vos. The drain characteristics are similar to…

is attached to a line that is separated from the rest of the symbol, to emphasize that the gate is insulated from the channel. The square-law equation for the transfer characteristic of a depletion-type Samoset is identical \0 that for a Forget: This equation correctly predicts Iv when the depletion-type SAMOSET is operated in. the enhancement…

The metal-oxide-semiconductor GET (SAMOSET) is similar in many respects to its JFET counterpart, in that both have drain, gate, and source terminals, and both are devices whose channel conductivity is controlled by a gate-to-source voltage. The principal feature that distinguishes a from a JFET is the fact that the gate terminal in a is insulated…

MANUFACTURER’S DATA SHEETS Figures 7-25 and 7-26 show typical data sheets for a series of N-channel JFETs: the 2ND, I , and 2ND. Note in particular the specification for the range of values of loss for each device, as shown in Figure 7-25. We see, for example, that loss for the can range from 5…

The general form Dr the algebraic solution for the bias point in a voltage-divider bias circuit can be found by solving the square-law equation (7-2) simultaneously with the bias-line equation (7-11 or 7-)2)_ The results, shown in equations 7-13, are valid for both P-channel and N-channel devices, since absolute values are used in the computations.…

Thus, (-3 Y, 5 mA) is another point on the bias line. We can then draw a straight line between the two points (0,0) and (- J V, 5 mA) and note where that line intersects the transfer characteristic. The line is plotted on the-transfer characteristic shown in Figure 7-17. We note that it intersects…

Equations 7-4 are the equations of the load lines for N- and P-channel JFETs and each can be plaited on a set of drain characteristics to determine a Q-point. This technique is the same as the one we used to determine the Q-point in a BJT bias circuit. The load line intersects the Vos-axis at…

Transfer Characteristics The transfer characteristic of a lFET is a plot of output current versus input voltage. for a fixed value of output voltage. When the input to a JFET is the gate-to-source voltage and the output current is drain current (common-source configuration). the transfer characteristic can be derived from the drain characteristics. It is…

which is the saturation current at. the V us =V line (see Figure,7-5(b)). Note in Figure 7-6 that the region to tHe right ol.the, parabola-is called the pinch-off region. This is the region in which 1he JFET is normally-operated when used -for small-signal amplification. It is also called the active region;or the saturation region. The…